Metal whisker growth induced by localized, high-intensity DC electric fields

MRS Advances ◽  
2018 ◽  
Vol 3 (57-58) ◽  
pp. 3367-3372
Author(s):  
Vamsi Borra ◽  
Osama Oudat ◽  
Daniel G. Georgiev ◽  
Victor G. Karpov ◽  
Diana Shvydka
Keyword(s):  
Electric Fields ◽  
Whisker Growth ◽  
Dielectric Breakdown ◽  
Extended Period ◽  
Growth Direction ◽  
Separation Distance ◽  
Vertical Orientation ◽  
Conductive Afm ◽  
Sample Separation ◽  
Very High

ABSTRACTIn this work, a very high, locally applied electric field was used to induce whisker nucleation on an Sn film. The field was generated by using a conductive AFM tip and applying a voltage bias between the sample and the conductive cantilever. The tip-sample separation distance was thus controllable, and any dielectric breakdown could be avoided. At locations where the AFM tip was positioned for an extended period, minuscule whiskers were observed, whose growth direction matched vertical orientation of the field.

Time-Dependent Dielectric Breakdown in Thin Intrinsic SiO2 Films

1995 ◽  
Vol 386 ◽  
Author(s):  
J. S. Suehle ◽  
P. Chaparala
Keyword(s):  
Electric Field ◽  
Electric Fields ◽  
High Temperatures ◽  
Dielectric Breakdown ◽  
Operating Conditions ◽  
Time Dependent ◽  
Stress Tests ◽  
Time Dependent Dielectric Breakdown ◽  
Wide Range ◽  
Very High

ABSTRACTTime-Dependent Dielectric Breakdown studies were performed on 6.5-, 9-, 15-, 20-, and 22.5- nm thick SiO2 films over a wide range of stress temperatures and electric fields. Very high temperatures (400 °C) were used to accelerate breakdown so that stress tests could be performed at low electric fields close to those used for device operating conditions. The results indicate that the dependence of TDDB on electric field and temperature is different from that reported in earlier studies. Specifically, the electric-field-acceleration parameter is independent of temperature and the thermal activation energy was determined to be between 0.7 and 0.9 eV for stress fields below 7.0 MV/cm.Failure distributions of high-quality current-generation oxide films are shown to be of single mode and have dispersions that are not sensitive to stress electric field or temperature, unlike distributions observed for oxides examined in earlier studies. These results have implications on the choice of the correct physical model to describe TDDB in thin films. The data also demonstrate for the first time the reliability of silicon dioxide films at very high temperatures.

Time-Dependent Dielectric Breakdown in Thin Intrinsic SiO2 Films

1995 ◽  
Vol 391 ◽  
Author(s):  
J. S. Suehle ◽  
P. Chaparala
Keyword(s):  
Electric Field ◽  
Electric Fields ◽  
High Temperatures ◽  
Dielectric Breakdown ◽  
Operating Conditions ◽  
Time Dependent ◽  
Stress Tests ◽  
Time Dependent Dielectric Breakdown ◽  
Wide Range ◽  
Very High

AbstractTime-Dependent Dielectric Breakdown studies were performed on 6.5-, 9-, 15-, 20-, and 22.5-nm thick SiO2 films over a wide range of stress temperatures and electric fields. Very high temperatures (400 °C) were used to accelerate breakdown so that stress tests could be performed at low electric fields close to those used for device operating conditions. The results indicate that the dependence of TDDB on electric field and temperature is different from that reported in earlier studies. Specifically, the electric-field-acceleration parameter is independent of temperature and the thermal activation energy was determined to be between 0.7 and 0.9 eV for stress fields below 7.0 MV/cm.Failure distributions of high-quality current-generation oxide films are shown to be of single mode and have dispersions that are not sensitive to stress electric field or temperature, unlike distributions observed for oxides examined in earlier studies. These results have implications on the choice of the correct physical model to describe TDDB in thin films. The data also demonstrate for the first time the reliability of silicon dioxide films at very high temperatures.

A STUDY OF THE ELECTRICAL PROPERTIES OF Al2O3 FILMS DEPOSITED ON GaAs SUBSTRATES BY SPRAY PYROLYSIS

2002 ◽  
Vol 09 (05n06) ◽  
pp. 1637-1640 ◽  
Author(s):  
J. CHAVEZ-RAMIREZ ◽  
M. AGUILAR-FRUTIS ◽  
M. GARCIA ◽  
E. MARTINEZ ◽  
O. ALVAREZ-FREGOSO ◽  
...  
Keyword(s):  
Aluminum Oxide ◽  
Spray Pyrolysis ◽  
Electric Fields ◽  
Dielectric Breakdown ◽  
Spray Pyrolysis Technique ◽  
Interface State ◽  
State Density ◽  
Oxide Semiconductor ◽  
Electrical Characteristics ◽  
Gaas Substrates

Electrical characteristics of high quality aluminum oxide thin films deposited by the spray pyrolysis technique on GaAs substrates are reported. The films were deposited using a spraying solution of aluminum acetylacetonate in N,N-dimethylformamide and an ultrasonic mist generator. The substrates were (100) GaAs wafers Si-doped (1018 cm -3). The substrate temperature during deposition was in the range of 300–600°C. The electrical characteristics of these films were determined by capacitance and current versus voltage measurements by the incorporation of these films into metal-oxide-semiconductor structures. The interface state density resulted in the order of 1012 1/ eV-cm 2 and the films can stand electric fields higher than 5 MV/cm, without observing a destructive dielectric breakdown. The refractive index, measured by ellipsometry at 633 nm, resulted close to 1.64. The determination of the chemical composition of the films was achieved by energy dispersive X-ray spectroscopy; it resulted close to that of stoichiometric aluminum oxide (O/Al = 1.5) when films are deposited at substrate temperatures of 300–350°C.

Electroreception in Gymnotus carapo: pre-receptor processing and the distribution of electroreceptor types

2000 ◽  
Vol 203 (21) ◽  
pp. 3279-3287 ◽  
Author(s):  
M.E. Castello ◽  
P.A. Aguilera ◽  
O. Trujillo-Cenoz ◽  
A.A. Caputi
Keyword(s):  
Electric Fields ◽  
Electric Fish ◽  
Fish Tissue ◽  
Field Vector ◽  
The Body ◽  
Type I ◽  
Type Ii ◽  
Field Patterns ◽  
Different Types ◽  
Very High

This paper describes the peripheral mechanisms involved in signal processing of self- and conspecific-generated electric fields by the electric fish Gymnotus carapo. The distribution of the different types of tuberous electroreceptor and the occurrence of particular electric field patterns close to the body of the fish were studied. The density of tuberous electroreceptors was found to be maximal on the jaw (foveal region) and very high on the dorsal region of the snout (parafoveal region), decaying caudally. Tuberous type II electroreceptors were much more abundant than type I electroreceptors. Type I electroreceptors occurred exclusively on the head and rostral trunk regions, while type II electroreceptors were found along as much as 90 % of the fish. Electrophysiological data indicated that conspecific- and self-generated electric currents are ‘funnelled’ by the high conductivity and geometry of the body of the fish. These currents are concentrated at the peri-oral zone, where most electroreceptors are located. Moreover, within this region, field vector directions were collimated, constituting the most efficient stimulus for electroreceptors. It can be concluded that the passive properties of the fish tissue represent a pre-receptor device that enhances exafferent and reafferent electrical signals at the fovea-parafoveal region.

scholarly journals Significantly Improved Electrical Properties of Crosslinked Polyethylene Modified by UV-Initiated Grafting MAH

Polymers ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 62 ◽  
Author(s):  
Xin-Dong Zhao ◽  
Hong Zhao ◽  
Wei-Feng Sun
Keyword(s):  
Electric Fields ◽  
Carrier Transport ◽  
Elevated Temperatures ◽  
Dielectric Breakdown ◽  
Breakdown Strength ◽  
Electrical Conductance ◽  
Electrical Current ◽  
Underlying Mechanism ◽  
Polar Group ◽  
Frenkel Effect

Direct current (DC) electrical performances of crosslinked polyethylene (XLPE) have been evidently improved by developing graft modification technique with ultraviolet (UV) photon-initiation. Maleic anhydride (MAH) molecules with characteristic cyclic anhydride were successfully grafted to polyethylene molecules under UV irradiation, which can be efficiently realized in industrial cable production. The complying laws of electrical current varying with electric field and the Weibull statistics of dielectric breakdown strength at altered temperature for cable operation were analyzed to study the underlying mechanism of improving electrical insulation performances. Compared with pure XLPE, the appreciably decreased electrical conductivity and enhanced breakdown strength were achieved in XLPE-graft-MAH. The critical electric fields of the electrical conduction altering from ohm conductance to trap-limited mechanism significantly decrease with the increased testing temperature, which, however, can be remarkably raised by grafting MAH. At elevated temperatures, the dominant carrier transport mechanism of pure XLPE alters from Poole–Frenkel effect to Schottky injection, while and XLPE-graft-MAH materials persist in the electrical conductance dominated by Poole–Frenkel effect. The polar group of grafted MAH renders deep traps for charge carriers in XLPE-graft-MAH, and accordingly elevate the charge injection barrier and reduce charge mobility, resulting in the suppression of DC electrical conductance and the remarkable amelioration of insulation strength. The well agreement of experimental results with the quantum mechanics calculations suggests a prospective strategy of UV initiation for polar-molecule-grafting modification in the development of high-voltage DC cable materials.

Long-term can-sealing protection: a stable black phosphorus nanoassembly achieved through heterogeneous hydrophobic functionalization

Nanoscale ◽  
2021 ◽  
Author(s):  
Ying-Hao Pai ◽  
Chun-Hua Chen
Keyword(s):  
Extended Period ◽  
Black Phosphorus ◽  
High Humidity ◽  
Rapid Degradation ◽  
High Humidity Environment ◽  
Very High ◽  
Humidity Environment

Hydrophobic Al2O3 columnar cappings have been demonstrated as promising candidates for comprehensive protection against severe rapid degradation of pristine black phosphorus even under a very high-humidity environment (RH = 85%) for an extended period.

scholarly journals Nanosecond air breakdown parameters for electron and microwave beam propagation

1988 ◽  
Vol 6 (1) ◽  
pp. 105-117 ◽  
Author(s):  
A. W. Ali
Keyword(s):  
Electric Fields ◽  
Drift Velocity ◽  
Collision Frequency ◽  
Short Pulse ◽  
Microwave Beam ◽  
Avalanche Ionization ◽  
Air Breakdown ◽  
High Electric Fields ◽  
Ionization Frequency ◽  
Very High

Air breakdown by avalanche ionization plays an important role in the electron beam and microwave propagations. For high electric fields and short pulse applications one needs avalanche ionization parameters for modeling and scaling of experimental devices. However, the breakdown parameters, i.e., the ionization frequency vs E/p (volt. cm−1. Torr−1) in air is uncertain for very high values of E/P. We review the experimental data for the electron drift velocity, the Townsend ionization coefficient in N2 and O2 and develop the ionization frequency and the collision frequency for momentum transfer in air. We construct the E/p vs Pτ diagram and show that our results are in better agreement with the most recent short pulse air breakdown experiments, compared to those predicted by the expression of Felsenthal & Proud (1965). This is because they extrapolate an expression for the drift velocity, linear in E/p, to high values of E/p. Experimentally the drift velocity varies as (E/p)½ in the region of E/p > 100.

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